Disinsection system and cartridge for use therewith



J. A. JENSEN Dec. 22, 1970 DISINSECTION SYSTEM AND CARTRIDGE FOR USETHEREWITH 2 Sheets-Sheet l Filed May 23, 1969 00000 s000000 309000 wvvvJ. A. JENSEN Dec. 22, 1970 l DISINSECTION SYSTEM AND CARTRIDGE FOR USETHEREWITH Filed May 23, 1969 2 Sheets-Sheet /M/EA/m,

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United States Patent 3,548,533 DISINSECTION SYSTEM AND CARTRIDGE FOR USETHEREWITH Jens A. Jensen, Savannah, Ga., assignor to the United Statesof America as represented by the Secretary of the Department of Health,Education, and Welfare Filed May 23, 1969, Ser. No. 327,352 Int. Cl.A01m 13/00 U.S. Cl. 43-129 11 Claims ABSTRACT 0F THE DISCLOSURE Adisinsection system, particularly for use in pressurized aircraft,comprising a one shot cartridge containing a predetermined quantity of amixture of a propellent and an active material, preferably, dichlorvos,a manifold and support assembly for receiving the cartridge andautomatically spraying the active material onto an absorbent filtermeans within the cartridge, a motor-compressor unit for feedingpressurized carrier air into lthe cartridge, through the filter means topick up a quantity of the active material and to heated distributionconduit means for carrying the air-active material mixture to locationsremote from the cartridge. A control unit is provided for delayingactivation of the compressor means and conduit heater means for a timesufficient to insure complete absorption of the active material by thefilter means and a timer unit which automatically deactivates the systemwhen disinsection has been completed.

This application relates to disinsection systems and cartridges thereforand relates more particularly to a disinsection system for use inaircraft.

The disinsection of aircraft is quite important as a preventativemeasure against transporting disease vectors from one country toanother. Actually, the problem of destroying insects in aircraft isrelatively simple in the abstract, but from a practical standpointdifficulties are encountered since it is necessary to utilize a systemwhich causes a minimum of interference to traffic operation and aminimum of discomfort to the passengers and crew. Treatment withaerosols based primarily on pyrethrum and DDT, sometimes supplementedWith residual deposits of DDT, had been the accepted practice for manyyears even though it became increasingly evident that aerosol treatmentswere far from adequate in many respects. Some of the major weaknesses ofthe aerosol method are the difficulty of insuring that treatment hasbeen carried out effectively, the discomfort caused to passengers, andthe questionable effectiveness of the aerosols against insects under theconditions encountered in practice. This latter inadequacy is probablythe most important. Tests have shown that in loaded baggage compartmentscornplete kills of free-flying houseflies were not obtained with adosage of aerosol as high as 600 g. per 1000 cubic feet, the recommendeddosage of 5 g. per 1000 cubic feet in passenger compartments being shownconsistently to give poor kills of the free-flying houseies exposed tothe treatment in aircraft in flight.

Additionally, the development of resistance to certain aerosols such asDDT provides another inadequacy to such systems. More recently a newvolatile organic phosphorous jcompound commonly called dichlorvos(2,2-dichlorovinyl dimethyl phosphate, also called DDVP) has provided amaterial which is entomologically effective without passengers in anaircraft being aware of its presence. However, in order for suchmaterial to be useful it is necessary to provide a suitable distributionsystem.

Prior art techniques of aircraft disinsection utilizing aerosolsinvolved spraying the cabin and baggage com- Patented Dec. 22, 1970 ICCpartments with such material. It was found that the best time foreffective application of such aerosols in the passenger cabin was afterthe embarkation of passengers and the closing of doors, but beforetake-off. The pilots cabin was disinsected prior to their entry andcargo and baggage compartments Were treated just before take-off. Thistechnique was called blocks away and can be effective if carefullyapplied, presuming that the insects had not developed resistance to theinsecticide used. However, the difficulties in careful application ofsuch a system are believed obvious in that the insecticide in aerosolstate is particulate and must be directed into cabin baggage racks,clothes hanging areas, toilets, etc. for complete use. Further, theblocks away method is considered impractical for disinsection of largesuper-jet aircraft.

The effectiveness of an insecticidal vapor treatment is a function ofthe concentration of the toxicant and the dura.. tion of exposure of theinsects, Toxic concentrations of an insecticide are difficult tomaintain in an aircraft Where the cabin air is renewed continuously,oftentimes once every two to three minutes. Under these conditions anymomentary treatments such as the use of pressurized aerosols isinadequate. Further, even with the use of a vapor disinsectant such asdichlorvos, uniform distribution of the vapor throughout the space to bedisinsected to maintain a toxic concentration for sufficient period toinsure complete kill of disease vectors is necessary.

Various prior art references disclose cartridges in which an insecticideor the like is sprayed onto an absorbent matrix, but such devices aredesigned to operate spontaneously and the rate of vaporization isvariable being governed by the humidity, the tempearture and naturalconvection. Dichlorvos is readily hydrolyzed by moisture and forms anonvolatile compound (dimethyl phosphoric acid) which covers theVaporizing surface and acts as a barrier to the vaporization anddiffusion processes. Thus, a marked decline in output occurs over ashort period of time and spontaneous systems of the prior art type areunable to deliver biologically effective vapor concentrations.

Dichlorvos or other such volatile insecticides cannot be properlydispensed unless a cartridge containing the same is utilized incombination with a disinsection system capable for carrying controlledvolumes of air at controlled and predetermined temperatures through amatrix of which the dichlorvos is absorbed, The factors which controlthe rate of vaporaization are (l) the volume of air passing through thematrix to carry the vapor away and furnishing the heat of vaporizationof the volatile insecticide, (2) the temperature of the carrier air, (3)the amount of liquid insecticide on the matrix, and (4) the surface areaof the matrix from which the vapors emanate. A suitable disinsectionsystem must properly control all of the foregoing factors and, when usedin aircraft, must provide preselected values to produce a predeterminedvapor concentration which can be maintained in the space to bedisinsected even though the space may be ventilated continuously asexperienced in aircraft. In order for a disinsection system to beadequate for the purposes intended it must be capable of maintaining abiologically effective concentration of the insecticide for one halfhour or longer.

Thus, it is a primary object of the instant invention to provide adisinsection system and a cartridge for use therewith which functions tocontrol all of the variables ordinarily encountered to produce thenecessary vapor concentration over an extended period. Further, thisinvention provides a cartridge which, when used with the disinsectionsystem hereof, is effective to produce vapor at a rate as much as 40 mg.per minute, this rate being unobtainable with spontaneous vaporizers ofthe prior art type which are incapable of delivering the largequantities of vapor needed for maintenance of a biologically effectiveconcentration for aircraft or other such disinsection purposes sincesuch prior art devices result in a build up of decomposition productsfrom hydrolysis which slows the vaporization rate to unacceptablelevels.

It is a further object of this invention to provide a cartridge for usein a disinsection system which is a one shot unit designed to operate ata high rate of output for approximately thirty minutes. Distribution ofinsecticide vapor spontaneously would take substantially longer periodsof time, the time period utilized with the disinsection system of theinstant invention being sufliciently limited to prevent any appreciablehydrolysis that would affect the rate of output.

It is yet another object of this invention to providea cartridge anddisinsection system wherein it is impossible to lose control of theactive material by spills, wherein it is impossible to produce thecontact with the skin of the operator of the system by the insecticideor accidental breathing of concentrated vapor because the insecticidematerial is always trapped either in a miniature pressure vessel or in afilter matrix and the vapors are removed from the cartridge only byforcing carrier air through the matrix.

A further object of the instant invention is the provision of adisinsection system which is fail safe and operated at its maximumcapacity, the capacity being readily adjustable to meet the requirementsof a certain type and size of aircraft or other space to be disinsected.With the system of the instant invention any malfunction or failureresults in a lower output of vapor or a complete cessation of output.Since all insecticides, including dichlorvos, are toxic to humans tosome extent, it is mandatory that the system is fully controllable tokill the insects without adversely affecting the passengers or crew inan aircraft, this absolute control of the vaporization of theinsecticide being the crux of the system of the instant invention andthe cartridge utilized therewith.

A still further object of the instant invention is the provision of adisinsection system which requires relative small amounts of activematerials, it simple and inexpensive to manufacture and maintain, highlydurable in construction and reliable in use.

Another important object of this invention is the provision of adisinsection system which is substantially automatic in use requiringlittle training of operators to insure proper control, the operatormerely attaching a cartridge containing the active material to thesystem and pressing a button, the system including means to delaypassage of carrier air through the cartridge for a time sufiicient toinsure complete dispening of the active material onto the filter matrixand further including means to automatically deactivate the operatingmechanism after a period sufficient to insure that the active materialhas been cornpletely distributed throughout the space to be disinsected.

Other and further objects reside in the combination of elements,arrangement of parts and features of construction. Still other objectswill in part be obvious and in part be pointed out as the description ofthe invention proceeds and as shown in the accompanying drawingswherein:

FIG. l is a schematic illustration of the overall disinsection system ofthe instant invention;

FIG. 2 is an enlarged fragmentary view of a portion of the distributionconduit means utilized in this system, partly in cross-section forillustrative clarity;

FIG. 3 is an enlarged cross-sectional View of the cartridge, manifoldand support assembly utilized in the disinsection system of the instantinvention;

FIG. 4 is a transverse cross-sectional view taken substantially on lines4-4 of FIG. 3; and

FIG. 5 is an enlarged cross-sectional view through another form ofnozzle means which can be utilized with the cartridge of this invention.

Like reference characters refer to like parts throughout the severalviews of the drawings.

`Referring now to the drawings, and more particularly to FIG. l, adisinsection -system in accordance with the instant inventive conceptsis schematically shown and designated generally by the reference numeral10, an aircraft or other means defining the space to be disinsectedbeing schematically illustrated by the dot-dash lines designated by thereference numeral 15. The system 10 comprises basically five majorcomponents, a single use insecticide cartridge designated generally bythe reference numeral 20, a manifold and support assembly therefordesignated generally by the reference numeral 25, a motor-compressorunit designated generally by the reference numeral 30, vapordistribution conduit means designated generally by the reference numeral3-5 and an electrical control unit schematically illustrated within thedotted lines 40.

Further details of the cartridge 20` andthe manifold and supportassembly 25 are shown in FIG. 3 and 4. The cartridge 20 comprisesbasically a housing means 42 including an imperforate peripheral sidewall 44, a closed base portion 46 and an oppositely disposed, taperedopen neck portion 48. A pressurized vessel in the form of a Iminiatureaerosol container 50 is seated within an offset flange 52 of the baseportion 46 of the housing means 42 and retained therein by plate 54. Asuitable quantity of a mixture of a propellent such as Freon 12(dichlorodiuoromethane) and an active material such as dichlorvos iscontained within the vessel 50, the active material being dispensed fromthe vessel 50 under the pressure of the propellant on actuation of anormally closed valve means 56 operatively associated with the vessel.The valve means 56 may take any conventional form and is actuated bypressure thereagainst to open the same in a manner to be described inmore detail hereinafter.

A nozzle means '58` is operatively associated with the valve means forspraying the dispensed active material toward the peripheral side wall44 of the housing means 42. 'I'he nozzle means 58 may merely be in theform of a chamber having a plurality of apertures 60` therein such asshown in PIG. 3 or, alternatively, may take the form shown in FIG. 5 at58 which includes a base element 62 having a conical depression 64 witha conical dispersing element 66 positioned in spaced relationshipthereto by a grooved stem 68 press fit into a bore 70 within the baseelement `62 to provide a peripheral spray channel 72 between theelements 62 and 66. The nozzle means 58 forms no part of the instantinvention and is only illustrated as a suitable and sometimes preferred,substitute for the nozzle means 58.

A filter means, preferably in the form of a pleated paper filter member75 is interposed between the nozzle means 58 and the peripheral sidewall 44 of the housing means 42 for absorbing the active materialsprayed from the nozzle means 58. Other suitable filter means may besubstituted for the pleated paper member illustrated in the drawings andit is to be understood that the filter means can adsorb as well asabsorbed the active material sprayed from the nozzle means 58. In theillustrated embodiment the pleated paper filter member 75 extendsbetween, and may be adhesively attached to, the base portion 46 of thehousing means 42 and an end plate 76 carried by a foraminous shell 78 inthe form of a wire mesh or perforated metal element.

An elastromeric gasket means 8f) is carried by the end plate 76 for apurpose to be described in more detail hereinafter.

It will be seen that a first chamber `82 is defined between the outersurface of the filter means 7S and the inner surface of the peripheralside wall 44 of the housing means 42 and a -second chamber 84 is definedinteriorly of the filter means 75. Thus, after absorption of the activematerial by the filter means 75, a pressurized carrier gas can be fedinto the cartridge 20* to one of the chamber means in a manner to bedescribed in more detail hereinafter, through the filter means 75 to theother of the chamber means and out of the cartridge to thereby pick up aquantity of the active material from the filter means 75 and deliver thesame to a location remote from the cartridge 20k under controlledconditions.

The manifold and support assembly includes support means for removablyreceiving and holding the cartridge 20 in the form of a support sleevey85 which surroundingly engages at least a portion of the peripheralside wall 44 of the housing means 42 of the cartridge 20y andaquick-disconnect coupling means 86 removably engaging the neck portion48 of the housing means 42. The quick-disconnect coupling means 86, inthe embodiment Ishown, includes a plurality of ball bearings 88 normallyurged by spring means 90 into locking engagement with a peripheralgroove 92 defined about the neck portion 48 of the housing means 42. Anelastomeric gasket means 94 is carried by the manifold and supportassembly 25 to sealingly engage the end of the neck portion 48 of thehousing means `42 when the cartridge 20 is received by the manifold andsupport assembly 25.

The manifold portion of the manifold and support assembly 25 includes aninlet 95 communicating the first chamber 82 with a source of a carriergas under pressure to be ldescribed in more detail hereinafter, andfurther includes an outlet 96 communicating the second chamber means `84with the conduit means 35. An elongated hollow element 98 is secured atone end 100 in communication with the outlet 96 and has its opposite endportion 102 extending into the `second chamber means 84 when thecartridge 20 is received and held by the manifold and support assembly25. The end portion 10-2 includes a plurality of spaced apertures 104communicating the interior of the hollow element 98 with the -secondchamber means 84. As will be seen particularly from FIG. 3 the gasketmeans 80 carried by the cartridge 20` sealingly engages about theexterior of the hollow element 98 in sapced relationship to the endportion 102 to segregate the first and second chamber means 82, `84respectively.

A trigger means 106 is carried by the end portion 102 of the hollowelement 98 and includes a stud 10-8 threadably received in a guide nut110 on the end portion 102 of the hollow element 98, with the oppositeend of the stud 108 carrying a cup 112 in which is press fit a resilientbutton 114 adapted to pressingly engage the nozzle means 58 and thus thevalve means 56 upon insertion of the cartridge 20 into the manifold andsupport assembly 25 thereby automatically opening the valve means 56 andspraying the active material from the nozzle means 58 onto the filtermeans 75.

Referring again to FIG. l the motor-compressor unit preferably comprisesan electrically driven integral unit which, when the disinsection systemis utilized in an aircraft, is operated by available aircraft power toproduce the required amount of compressed carrier air. Basically, thisunit includes an electrically operated motor means 125 which drives aircompressor means 130' in any conventional manner, a source of air forthe compressor 130 being shown at 132 and a duct 134 for communicatingthe outlet of the compressor means 130 with the inlet 95 of the manifoldand support assembly 25 to feed compressed carrier air to the firstchamber 82 within the cartridge 20 and through the filter means 715 tothe second chamber 84 from which it passes through the apertures 104 inthe elongated element 98 to the outlet 96 of the manifold and supportassembly 25 and thence to the conduit means for distribution throughoutthe aircraft.

An enlarged portion of the conduit means 35 is shown in FIG. 2. andpreferably comprises a thin walled stainless steel tubing 135 coatedwith a layer of insulation 136, a conducting material such as electricalresistance wires 138 and an outer coating of insulation 140.Distribution nozzles 142 are press fit into the conduit means 35 atdesired locations.

The duct 134 from the compressor 130 may be heated in a manner similarto that described for the conduit means 35 if desired or necessary toproperly control the temperature of the air being fed to the cartridge20'.

The control means 40 preferably comprises a three phase source ofelectrical power 145, an appropriate circuit breaker 146, an overrideswitch 148, a thermal delay relay 150, a locking relay 152, a powerswitching relay 154, an electrical timer, self-setting and equipped witha circuit breaking switch schematically, shown at 156, a momentary pushbutton switch 158 and an indicator light 160. Additionally, a digitalelapsed time indicator (not shown) may be included in the circuitry ifdesired to maintain a record of the total time of operation of thedisinsection system.

The disinsection system of the instant invention operates as follows.The operator, for example a flight attendant in an aircraft, closes theoverride or on-off switch 148, inserts a cartridge 20 in the manifoldand support assembly 25 and then presses the momentary push buttonswitch 158 to activate the system. This completes the manual operationand the system then proceeds automatically in the following manner. Assoon as the cartridge 20 is inserted into the manifold and supportassembly 25 it is interlocked securely with the quick-disconnectcoupling means 86 and the trigger means 106 presses against the nozzlemeans 58 which in turn presses the valve means 56 to open the same andspray the active material onto the filter means 75. Of course, thequantity of ingredients contained within the vessel 50' can be varied,but it has been found that a preferred design incorporates approximatelythree ml. (4 g.) of dichlorvos and ten ml. of Freon l2 into the vessel50, and the discharge being completed in approximately ten seconds withthe filter means 75 completely absorbing and trapping the liquiddichlorvos in this time.

When the momentary push button switch 158 is pressed, current is passedto the locking relay 152 which maintains the switch 152' closed eventhough switch 158 is released. However, the thermal relay 150 takesapproximately twenty seconds to be sufficiently heated to close theswitch 150 thereby energizing the power switching relay 154 and closingthe switches 154 to activate the motor and the electrical resistancewires 138 surrounding the conduit means 35. In this manner, carrier gasin the form of compressed air is not fed to the cartridge 20 untilsufficient time has passed to insure that the active material within thevessel 50 has been completely dispensed and absorbed by the filter means75.

The Warm cabin air from the compressor means vaporizes the dichlorvosand carries the vapor through the conduit means 35 to all pressurizedareas of the aircraft 15, different branches of the conduit means 35extending, for example, to the cabin, the baggage compartments and theflight deck of the aircraft.

The required output from the compressor means 130 is designed to beproportional to the aircraft volume to be treated and variations may beobtained by a bleed air nozzle (not shown) in the compressor outletwhich may be adjusted during installation to limit the air passingthrough the cartridge 20 to that required for disinsection of theparticular aircraft.

The conduit means 35 are heated as indicated to prevent condensation ofthe dichlorvos on the inner surface of the tubing 135. The conduit means35 can be provide in preselected section lengths which may be butted andjoined with Teflon sleeve-bellows (not shown) to form a continuousheated tube of the desired length, with the heating elements of eachtube being a complete unit and the units being electrically connected inparallel. The distribution nozzles 142 may be spaced uniformly asneeded, for example, every forty inches, these nozzles preferably beingof nylon plastic and being pressed into openings in the conduit means.

The dichlorvos or other active material vapor leaves the conduit meansthrough the distribution nozzles 142 4 with which it mixes immediately.There is a continuous removal of the dichlorvos-air mixture from theaircraft through exhaust valves and three to four minutes aftercompletion of the disinsection cycle the cabin air is free ofinsecticide.

The dichlorvos or other such insecticide is vaporized by the warm airfrom the compressor in an amount adequate for the maintenance of aconcentration lethal to insects. A temperature indicator (not shown)which changes color when the cartridge has been discharged may beattached to the outside of the housing means 42 and the cartridge isdesigned as a one shot device which cannot be refilled thereby providingevidence of proper disinsection of a given aircraft. The digital elapsedtime indicator which may show the nearest tenth of an hour that thesystem has been operated provides verification that disinsection hasbeen carried out.

After a given period of time, preferably approximately thirty minutesfor aircraft disinsection, the timer means 156 automatically breaks thecircuit opening the locking relay 152 which in turn opens the powerswitching relay 154 and deactivates the motor means 125 and the heatermeans 138 on the conduit means 35. Since the preferred timer means 156immediately resets itself for further use, a resistor means 162 may beincluded in the circuit to quickly withdraw current from the lockingrelay 152. In this manner the system is automatically cut off after apredetermined interval to preclude the possibility of overtreatment andto minimize the time during which the system components are operated.

The indicator light 160 is maintained on throughout the disinsectioncycle.

Thus, it will be seen that activation of the disinsection system of theinstant invention is relatively simple, requiring no more than aboutthirty seconds and, once activated, the system operates unattended andautomatically for the entire disinsection operation. If desired,multiple disinsection cycles can be utilized with a plurality ofindividual cartridges for larger volume spaces or, alternatively, largercartridges may be provided.

The instant system provides a carefully controlled disinsection of agiven space and is not in any way dependent on natural convection whichrender prior art spontaneous systems uncontrollable. The advantages ofthe disinsection system of the instant invention and the cartridge usedtherewith are now believed obvious.

Accordingly, what is claimed is:

1. A cartridge comprising a housing means including an imperforateperipheral side wall, a closed base portion, and an oppositely disposedopen neck portion, a pressurized vessel carried by said base portion ofsaid housing means, a `quantity of a mixture of a propellant and avaporizable active material within said vessel, a normally closed valvemeans operatively associated with said vessel for dispensing said activematerial from said vessel under the pressure of said propellant whensaid valve means is opened, a nozzle means operatively associated withsaid valve means for spraying said dispensed active material toward saidperipheral side wall of said housing means, a filter means interposedbetween said nozzle means and said peripheral side wall of said housingmeans for absorbing said active material sprayed Lfrom said nozzlemeans, a first chamber means defined between the outer surface of saidfilter means and the inner surface of said peripheral wall portion ofsaid housing means, and a second chamber means defined by the innersurface of said filter means, said nozzle means being disposed Withinsaid second chamber means, whereby, after absorption of said activematerial by said filter means, a pressurized carrier gas can be fed intosaid cartridge to one of said chamber means, through said filter meansto the other of said chamber means and out of said cartridge to therebypick up a quantity of said active material from said filter means anddeliver the same to a location remote from said cartridge undercontrolled conditions.

2. A disinsecting system comprising, in combination, a cartridgeaccording to claim 1, a source of a carrier gas under pressure, meanscommunicating said carrier gas source with one of said chamber means,conduit means including dispensing means at a location remote from saidcartridge, and means communicating said conduit means with the other ofsaid chamber means.

3. The disinsecting system of claim 2 wherein said active material isdichlorvos.

4. The disinsecting system of claim 3 for use in an aircraft, saidconduit means including branches extending throughout said aircraft, anddispensing nozzles carried by said conduit means at spaced locationsalong each of said branches.

5. The disinsecting system of claim 2 including a manifold and supportassembly, said manifold and support assembly including support means forremovably receiving and holding said cartridge, inlet meanscommunicating between said carrier gas source and said rst chambermeans, and outlet means communicating between said second chamber meansand said conduit means.

6. The disinsecting system of claim 5 wherein said support meansincludes a support sleeve surrounding engaging at least a portion ofsaid peripheral side wall of said housing means, and quick-disconnectcoupling means removably engaging said neck portion of said housingmeans.

7. The disinsecting system of claim 5 wherein said outlet means includesan elongated hollow element having one end portion extending into saidsecond chamber means when said cartridge is received and held by saidsupport means, said one end portion including apertures communicatingthe interior of said hollow element with said second chamber means, andgasket means carried by said cartridge and sealingly engaging about theexterior of said hollow element in spaced relation to said one endportion to segregate said first and second chamber means.

8. The disinsecting means of claim 7 further including trigger meanscarried by said one end portion of said hollow element, said triggermeans being of sufficient length to engage said nozzle means oninsertion of said cartridge into said support means and to press saidnozzle means against said valve means thereby opening said valve meansand spraying said active material onto said filter means.

9. The disinsecting system of claim 8 wherein said carrier gas source isa compressor means, said conduit means including heater means forheating the same, said cornbination further including control means foractivating said compressor means and said heater means, said controlmeans including delay means for delaying activation of said compressormeans and said heater means for a time sufficient `to insure that all ofsaid active material within said vessel is sprayed onto said filtermeans before carrier air is passed through said cartridge to saidconduit means.

10. The disinsecting system of claim 9 wherein said heater meansincludes resistance wires surrounding said conduit means.

11. The disinsecting system of claim 9 wherein said control meansfurther includes timer means for automatically deactivating saidcompressor means and said heater means after a predetermined period whensubstantially all of said active material has been removed from saidfilter means.

References Cited UNITED STATES PATENTS 3,027,678 4/ 1962 Whitney et al.43-125 3,330,481 7/1967 Dearling 239-47 FOREIGN PATENTS 1,140,883 1/1969 Great Britain. 441,863 l/ 1968 Switzerland.

WARNER H. CAMP, Primary Examiner

